Apparatus for curling containers



Jan. 22, 1957 G. A. MOORE APPARATUS FOR CURLING CONTAINERS INVENTOR.

Filed Jan. 18, 1954 APPARATUS FOR CURLING CONTAINERS George Arlington Moore, New York, N. Y.

Application January 18, 1954, Serial No. 404,417

12 Claims. (Cl. 93-365) This invention relates to improvements in apparatus for curling bodies of various shapes, and has particular reference to a tooled die embodiment with which to form the curl. The instant invention is particularly adapted for forming a helicoidal rim to the mouth of paper drinking cups and other types of conical shape containers.

Such conventional paper containers are usually curled with spinning tool crirnpers that revolve at excessive speed against a marginal portion of the container body, causing portions of the paper fibres to drift and break into lint dust which finds access to the mechanical working parts of the container fabricating machine in which the crirnpers function. The spinning crimper action upon the paper, generates considerable friction productive of excessive heat and hence causes wear that necessitates frequent replacement of crimper parts. A major part of the high maintenance costs of the machinery and tool equipment is in general attributed to the use of this method.

The present invention contemplates the replacement of such spinning tool methods as being no longer required, and provides for an improved apparatus device exemplified by the function of a simple tooled curling die capable of forming a helicoidal rim to the mouth of con tainers without requiring any spinning or rotating movement of any kind, the curling die being provided with means that forms the curled rim While being actuated longitudinally coincident with the mean axis of the tapering angle that is provided for the body wall of the particular container.

Another object of the instant invention is to provide means with which containers may be radially curled without generating frictional heat of any consequence.

A further object of the invention is to provide an improved device for curling paper bodies in such efiicient manner that the deleterious effects of centrifugal force is eliminated upon the paper bodies.

A still further object of this invention is to provide a strongly re-enforced rim to the mouth of containers having straight or tapering side walls, the rim being of helicoidal structure adapted for the engagement of a closure for the container.

Another object of the invention provides for novel apparatus for radially curling bodies of other than round shape, the device having adaptability to form an elongated curled rim structure to the bodies in general.

A further object of the instant invention is to provide paper drinking cups with a helicoidal rim to avoid exposure of the leading edge of the curl to liquids while drinking from the cup.

These and additional objects of the invention will be observed upon a consideration of the following description of a preferred embodiment of the invention and by reference to the accompanying drawings, in which Fig. 1 is a side view in cross-section of the tooled curling die taken on line 11 in Fig. 2, the view having broken parts,

tates Pate Patented Jan. 22, 1957 Fig. 2 is a front elevation of the die with parts in expanded position,

Fig. 3 is a view in part of the curling die in crosssection taken on line 3-3 in Fig. 4, the die parts being disposed in finishing position,

Fig. 4 is a front elevation in part of the curling die with parts in contracted position,

Fig. 5 is a fragmentary view in cross-secti0n of a tool part in open position,

Fig. 6 is a fragmentary part of a front elevation of a modified form of the curling die,

Fig. 7 is a fragmentary view of the curled container with a part of the wall broken away to view the helicoidal rim in cross-section, and

Fig. 8 is a fragmentary view in cross-section of a modilied form of curled structure.

The curling apparatus of this invention may be used by conventional container fabricating machinery, the tooled die functioning with two basic longitudinal motions, parts of the die being opposed by the end portion of a centrally positioned body to be curled. The die assembly 4 consists of a central shaft 5 which may be provided with means for actuated timing of the longitudinal motion by suitable cam action' The shaft is supported in a slidable sleeve 6 which may be provided with suitable cam timing means that will control the longitudinal motion independently of the said shaft motion. The shouldered end 7 of the shaft is aflixed with a truncated anvil body 8 being of substantially square cross section having dove-tail longitudinal slide bearings Ilt) central upon side walls 9, each of the side walls sloping inwardly toward each other at a pre-determined angle of taper to coincide wi.h the body of the container to be curled. Two opposed sides of the anvil 8 support two substantially identical curling segments 11 and the two adjacent sides support two other curling segments 12 which are substantially alike. Each of the said segments are provided with dove-tail slots adapted for anchoring the segments in such manner that they may have freedom for longitudinal movement upon the anvil. The segments are coupled together with flat plate splines 13 each being fastened in slots disposed in opposing sides of the two opposed curling segments 12, the adjacent segments 11 having slots in opposing sides to engage a por tion of each spline and have freedom of movement transversely of the longitudinal motion. The splines anchor the curling segments in alignment with each other transversely with respect to the longitudinal anchoring alignment thereof.

The face of each of the curling segments 11 and 12 are provided with a semi-circular radial groove portion 14 which joins the outer wall of a tapering nose portion 25 extending outwardly from the lower side of the groove. Each pair of curling segments are provided with moveable segment shoe plates 16 and 17 mounted to rocker arms 17 pivoted with pins llfi mounted in forked lugs 19 and 19' attached to the body of the segments 11 and 12. The shoe members 16 and 17 are each provided wi.h a semi-circular radial groove 14 disposed to face and concentrically align with the groove portion 14 of the said segments to form a circular radial cavity having an annulated entree opening 15' adjacent to a longitudinal wall portion of the nose 15. The rocker arms 17' are connected with compensating links 29 and operating rods 21 which slide through bearings provided in a spider housing 22 which is supported upon the end of the sleeve 6. The front wall of the spider is provided with upper and lower outwardly projected lug bosses 23 for attaching a pair of compensating links 24 connecting the forked lugs 19 of the curling segments with pivoting pins 25.

The tooled curling die assembly 4 in the position illustrated in 'Figs. 1 and 2, characterizes the relative focusing position of the die with respect to the mouth of the centrally positioned body 26 made ready for curling. The bodies or containers may be handled and supported if desired in the same manner as used with conventional spinning methods-hereinbefore described. The body 26 is held in stationary position and in concentric alignment with the nose portions 15 of the curling die segments, the tool assembly having moved forward with equal motion of the shaft 5 and sleeve 6 to insert the said nose portions into the mouth of the body wall. in this position the anvil 8 dwells at rest, the segments 11, 1-2 and shoes 16, 17 being spread apart leaving spaced gaps 28 between the sides of each segment due to the relatively high initial position provided for the'segments upon the tapered sidesof the anvil 8. The gaps 28 are positioned on the bias with respect to the semi-circular grooves 14, 14'. The sleeve 6 and spider housing 22 then moves forward giving longitudinal motion through the links 24 to each of the curling segments and shoes which entrains the end portion of the body wall 26 into curling engagements with the walls of the radial cavities. During the said longitudinal movement, the segments and shoes move transversely and progressively together the sides 29 of each segment meeting each other to form an annular radial cavity concentrically true with the body Wall. The bias of the open gaps 28 keeps the body wall margin in curling entrainment while the gaps 23 are closed, thus eliminating any undue friction at these regions of the curling grooves. When curling bodies having relatively steep angles of taper, the segments may be provided with a longer bias in relationship to the radial cavities.

The tooled curling die in finishing position is illust'rated in Figs. 3 and 4. The mouth of the body 26 is provided with a helicoidal rim of firm construction. At the completion of the curl, the rods 21 may be moved by any suitable cam action provided that will pull on the link connected rocker arms 17' to swing the shoes '16 and 17 outwardly and clear the curled rim for release of the said body from the curling die. The die with the segments remaining in contracted position is retracted by suitable motion provided for the shaft 5 with simultaneous motion of sleeve 6 supporting spider 22 that will withdraw-the end portions'of the contracted segments '11, 12 from the curled body; otherwise, if the segments were moved upon-the anvil 8, they would expand and swedge themouth of the body. While removing the curledbo'dy to provide a replacement body, the anvil 8 is further retracted by motion of the central shaft 5, and the curling segments are then retracted upon the anvil S by motion of the spider 22 to take their original positions upon the anvil. The rods 21 are then pushed forward to close the opened shoes to their original relative positions.

The thrust imposed upon the arcuate portions of the segment shoes 16 and 17 during the curling cycle, may be'opposed and balanced by providing suitable connection of the opposite ends of rods 21 so that each rod will'ride upon the dwell of a timing track that also will generate timing motion to the rods 21, alternatively if desired, the rods may be provided with mechanical means for actuating trigger latch action, the latches locking the shoes until the trigger releases the rods to open the shoes'for release of the curled body. The general thrust of the curling die imposed upon the wall of container bodies is relatively light until the annular radial cavity fills with material. The transversely disposed radius of the arcuated cavities may be determined by the thickness of body material for example, material .020 inch thickness maybe suitably accommodated for curling with a radius of one-sixteenth of an inch. Paper container bodies are usually made with relatively broad overlapping longitudinal seams. The amount of the overlapped material may be substantially reduced for the containers curled with the tooled curling die, inasmuch as the die does not function traverse to the longitudinal edge of the body seam, which is contrary to the conventional spinning methods usually employed. The overlapping seam of bodies in the region to be curled may be reduced to one-eighth of an inch if desired to provide economy in use of material.

The anvil body 8 may be equipped with drilled holes for insertion of low voltage calrod heating elements that may be used for heating the curling die if desired. The heat will act as a-lubricant when cur'lingpaper composed of relatively short fibres. The heating element sheaths may be about three-sixteenths inch diameter and provide suitable heating capacity with one hundred or more watts regulated for suitable temperature with eight to twelve volts of electrical current.

The curling segment parts may be made of any suitable material, for example, hardened and ground steel, the supporting anvil may be provided of suitable bronze material. The a'rcuate grooves of the parts are preferably highly polished to minimize friction, and when curling bodies that are treated with plastic materials -the arcuate walls of the'radial cavities may be initiallytreated with a baked on finish of Teflon that is constitutedto prevent thematerial from sticking to any part of the cavity while being curled. The heating means for the curling die hereinbefore described may be advantageously employed totemper bodies made of plastic sheet'material and render'them-pliable for curling purposes.

The descriptive reference hereinbefore given for the present invention is primary and relates in general to the curling of round conical shape containers. Within 'the scope of the inventiombodiesof other than round shape may be efficiently curled to'provide a helicoidal rim'to the mouth'of such bodies for an example, bodies of substantially rectangular'shape having fiat side wall portions with radial corner junctions as illustrated in Fig. 6 of the'drawing. The curling segments 32, 33 'and curling shoes 34, 35 provide for a traverse radial cavity 36 having two opposed'linear portions and two opposed adjacent linear'portions, each of the said portions'being joined together with circular shape corner junctions and form a'square with radialcorners.

Thefinished rim 37 ofthe body 38 is formed without the rotation of tools or of the body, the rim being helicoidalin structure which strongly re-enforces the mouth of the container. The edge of the body wall is imbricated to avoid exposure, the rirn'being well adapted to support a closure cap to the container. The curling die shoes 17 may be modified to curl an elongated rim 40 upon the body wall 41 illustrated in Fig. 8. This type of curled rim is suitable for the engagement of a closure cap adapted to close the mouth of the container.

Manufacturers of paper drinking cups have experimented for many years to overcome-problems that are inherent with curling spinning methods. They havetried various methods of curling to avoid spinning without accomplishing any practical commercial success, and particularly with reference to .a much wanted helicoidal type of curl. To the contrary, the instant invention provides an anomalous but etficientmethod with which to form helicoidal rims to the mouth of bodies.

The curling die of the present invention provides means with which to efficiently curl containers meansfor curlingcontainers having tapering body walls, the armate nose wall portions 15 of the segments 11. 12 c0ntrolling the lead of the container wall for entrainment into the'curling cavities of each of the said segments. The said cavity in each segment moves to maintain a mean radius coincident with the mean radius of the desired rim to be curled to the container body. The collective movement of the curling segmentscontrols the said arcuate wall portions and transverse curlingchaun'els to be always coincident-with the-taper of the container body wall while' being entrained and sheet a curl thereupon without dependence upon any rotary movement of either the body wall or the curling die,

The curling die may be modified for curling cylindrical shape bodies by combining the segments ll, 12 as a whole part leaving the curling shoes 16, 1'7 to function as hereinbefore described. The novel arrangement of the curling segments and shoes have adaptability for being modified to form curled rims to container bodies of substantially rectangular cross section but having radially adjoined corners. It will be further recognized that many changes in the structure and procedure described may be made without departing from the scope of the invention as defined in the appended claims.

I claim:

1. Apparatus for curling conically shaped containers which includes curling die comprising a central truncated body having four adjacent sloping sides to coincide with the angle of taper of the container side wall, each of said sloping sides being mounted with a slidable arcuate shaped segment part having a semi-circular groove disposed transversely of said sloping side, each arcuate shaped segment being attached with another arcuate shaped plate that is provided with a semi-circular groove facing the first mentioned groove to form a semi-circular annular hollow cavity having a cross sectional wall extending radially around more than three quarters of its circumference, said segments being combined as units and coupled together in spaced relationship to form separating slots disposed in bias relationship to said annular cavities, said truncated body being the means with which to register said annular cavities in said segments with a container body to be curled, said combined segments being adapted to move non-rotarily but longitudinally upon a marginal portion of the body of the container and entrain said marginal portion within said cavities, each of said cavities being adapted to move progressively and transversely coincident with the tapering wall of the corn tainer, said longitudinal and transverse movement meeting to effect a curled rim upon the mouth of the container.

2. A curling die for constructing a curled rim upon conically shaped paper containers, which comprises a central slidable truncated body having inclined side walls supporting two opposingpairs of slidable segment parts, said parts being initially spaced apart, each from the other, each spaced segment having an arcuate semicircular groove in the inner face thereof transverse of each respective supporting side wall, each of said arcuate shaped grooves being opposed and closed with an inverted grooved member to form a semi-circular radial cavity having an arcuate shaped narrow opening adjacent a protruding and inwardly sloping arcuate wall portion of the segment, said semi-circular radial cavity in each segment being collectively adapted to form an annular cavity having separating narrow gaps crossing said cavity on the bias, the coll ctive segments being adapted to slide upon their respective supporting inclined walls to register with the mouth of the container body wall and entrain a portion thereof within said collective cavities which gradually contract inwardly to close said bias gaps and form a continuous channel in which the entrainment of the body wall is concluded to efiect a curl upon said body.

3. A curling die according to claim 2 wherein upon the completion of the curl, each of said inverted grooved members is adapted to open outwardly of its related groove section for the release of the curled container body.

4. Apparatus for forming a helicoidal rim upon the periphery of comically shaped containers, which includes a movable substantially square truncated body having sloping side walls adapted to align opposing pairs of slidable arcuate shaped segments, each of said segments being provided with a transversely disposed semi-circular radial groove, each of said segments being also provided with another arcuate shaped connected and movable segment member that is provided with a semicircular groove inverted and facing said first mentioned groove so that an annular hollow cavity enclosure is formed in each of the combined segments having a circular Wall in cross section, said circular wall of the cavity being extended more than three quarters in circumference with respect to a complete circle, and the annular cavity having an annular shaped narrow opening adjacent sloping wall portions that project outwardly from each of the first mentioned arcuate shaped segments, each of the arcuate shaped combined segments being initially spaced apart with respect to the opposite side ends of their respective cavity, thereby providing an open gap between each segment that is biased across said annular cavity sections, said truncated body and segments being movable selectively and collectively to register and entrain a marginal portion of the container body wall within said annular substantially enclosed cavity, the segments being movable longitudinally against said body wall of the container in a direction that is continually coincident with the angle taper of the body wall while curling the entrained margin within said annular cavity, thereby forming a helicoidal curled rim upon said body wall of the container.

5. Apparatus according to claim 4 wherein each of said inverted arcuate shaped connected segment members is adapted to be opened outwardly of the slidable segments for the release of the completed rim of the container to be removed from the curl forming annular cavity enclosure.

6. Apparatus for curling the open mouth of conically shaped containers and providing an elongated U-shaped three-ply curled rim to be disposed upon the exterior side of the container body wall, which comprises sectionally divided and multiple semi-circular hollow shaped cavities that are formed of inverted combined portions defining substantially half parts of the elongated U-shape form of curl forming cavities, said cavities being transversely registered upon the end of the container body wall, a marginal portion of said body wall being entrained within said hollow cavities, said multiple cavities being movable against said body wall so that the cavities move in a longitudinal direction and at the same time move progressively inwardly to each other in transverse direction, each of said movements coacting to maintain the cavity register while curling the container to be coincident with the angle of taper of the body wall marginal portion being curled, said margin being directed to follow the wall contour of the cavities and thereby form a three-ply curled rim of elongated U-shape upon the open mouth periphery of the container.

7. Apparatus according to claim 6 wherein each of said sectionally divided cavities is formed in one of a plurality of slidable arcuate shaped segments, each segment having in the face thereof a semi-circular groove of elongated U-shape in cross section, a face portion of each segment also having attached thereupon an arcuate shaped segment having an inverted semi-circular groove of matching elongated U-shape in cross section that is provided with an opening in the inner side of said latter groove through which said body wall of the container is introduced into said hollow cavities, each of the first mentioned grooves and said inverted grooves forming the annular hollow cavity which entrains and forms said three-ply curled rim by sliding action of said segments moving the cavity against the end of said body Wall, said attached inverted groove segments being adapted to open so that said hollow annular cavity is momentarily parted for the release of the completed curled rim from said cavities.

8. Apparatus for curling the end of a substantially rectangular shaped container having tapered longitudinal side walls with converging radial corners comprising a central truncated body part having four adjacent sloping sides to coincide with the angle of taper of the container side walls, each of said sloping sides supporting a slidable segment member having a circular shaped groove disposed transversely of said sloping side, the shape of said groove in each segment being collectively extended in the shape coincident with said edge of the body wall of the container to be curled, each said segment member being connected with a second segment member that is provided with a circular shaped groove facing the first mentioned groove, thereby forming a hollow radial shape cavity having a wall in cross section extending around more than three quarters of -its circumference, said segments being combined as units and coupled together in spaced relation to form initial separating slots disposed in bias crossing relation to said hollow cavities, said truncated body providing means to register said cavities in the segments with the end edge of the container body to be curled, said combined segments being adapted to move non-rotarily but longitudinally upon a marginal portion of said container body and entrain the marginal portion of body wall within said cavities, each cavity being also adapted to move progressively transversely coincident with the tapering side walls of the container, said longitudinal and transverse movement co-acting to effect a curled rim extending continuously around the periphery of said side walls and radial corners thereof, said second segment members being adapted to open outwardly and thereby release said curled rim from the first mentioned members of said curl forming cavities.

9. A curling die of the character described for curling the edge of a container having a tapered body of substantially rectangular shape in horizontal cross section with radial shape connecting corners of substantially fiat side wall portions comprising an apparatus supporting body member movable relative to the container, segmental shaped curling members being slidably mounted upon surfaces of the supporting body member, said curling members having sectional parts combined therewith that provide a hollow curling cavity having a radial shaped wall in cross section extending around at least three quarters of its circumference, the transverse shape of said curling cavity being coincident with the cross sectional shape in general of the container body wall adjacent the top edge thereof, and means controlled by the first movement of said supporting body member and second independent sliding movement of said curling members that entrain said edge of the container body within each of th ir respective hollow curl forming cavities, said movement of the curling members being controlled to guide said curl forming members in a direction that is coincident with the particular taper of the container body wall, the curled rim being formed upon the rectangular shape of the body wall by being constructed and completed within said hollow cavities of the curling members, said members being provided with means for releasing said curled rim from the curl forming cavities prior to retracting movement thereof.

10. A curling die of the character described for the helicoidal curling of the edge of taper shaped bodies wherein the curl is formed and completed independently of body clamping parts, which includes a movable truncated body member having sloping sides coincident with the'taper angle of the body to be curled, said sides of the body member supporting longitudinally slidable segmental parts adapted to move independently of the movement of said supporting body member, each of said segmental parts being provided with a connected segmental movable econd part, the combined parts having an enclosed circular shaped hollow curling channel provided with a circular shaped wall in cross section that extends radially greater than a half circle, each of said first mentioned segmental parts having a protruding inner sloping Wall portion coincident with the taper of the body to be curled, and the longitudinal surface of the protruding wall being extended outwardly from the inner side of said hollow curling channel, the inner terminal ends of said second segmental parts being spaced outwardly transversely of said protruding wall portions thereby providing a relatively narrow opening into said hollow annular curling channel enclosure for entrance of the peripheral edge of the body to be curled, said truncated body member being first movable to align a marginal portion of said body to be curled over the protruding wall portions of said segmental parts supported thereupon, and upon arrested movement thereof, the combined segmental parts being then movable to entrain an aligned marginal body portion to be curled Within the hollow cavity channel enclosure, which channel is transverse of the entrained edge of the body, and the curl forming channels of said segmental parts, while effecting the curl upon said body, being movable longitudinally and progressively in a transverse direction that is controlled to be coincident with the taper of the entraining body wall portion, thereby completing a helicoidal curled rim confined within said hollow cavity annular channel enclosure, said second segmental parts being thereafter movable to temporarily open said curl forming channel enclosure to release said curled rim therefrom.

11. A device for curling the edge of a container body Wall, which includes a curling die consisting of four substantially flat segmental parts arranged in opposing pairs, each part of said pairs being slidably mounted and anchored upon a dove-tail slide upon the longitudinal side of a truncated body member, the front face of each segmental part being provided with a semi-circular radial shaped groove and a protruding wall portion being extended outwardly from the inner side of said groove, said wall portion having its exterior surface parallel to and in intimate contact with the body wall to be curled, each of said semi-circular grooves being faced with an inverted grooved member being connected with said first mentioned segmental part -to form a substantially enclosed curl forming semi-circular cavity having a radial shaped wall in cross section that extends around greater than three quarters of a complete circle, each inverted groove member having a semi-circular shaped end portion that is spaced outwardly of the transverse semicircular side of said protruding wall portion, thereby providing a semi-circular shaped opening into said curl forming cavity enclosure for entrance of said edge of body wall to be curled, one pair .of said segmental parts having oppOsi-te straight sides spaced in relation to straight side portions of the other pair of segmental parts thereby forming bias gaps at terminal ends of said curl forming semi-circular cavities that are substantially closed to arrange said semi-circular cavities in annular relationship upon longitudinal movement of the segmental parts, said parts being group controlled and stabilized by flat plate splines engaged in slots formed in the body of said parts and disposed transversely of their respective longitudinal movement, and upon a cycle of longitudinal movement, the co-action of said dovetail mounted segmental parts and plate splines providing means that guides said curl forming cavity enclosures in a group that will follow the particular shape of the container body wall While efiecting a curl thereupon.

12. A device for curling container bodies having substantially round or rectangular shape in body cross section, the device being self contained and including multiple segment parts each being provided with anarcuate shaped grooved cavity in the face portion thereof and the wall of said cavity being defined as having an initialtradial shape in cross section extending in excess of one hundred eighty degrees in circumference into which a marginal portion of a container body is to be entrained and curled, said multiple segments being slidably and transversely mounted upon longitudinal face portions of an independently movable truncated body part of said device, and two opposed aligned surface portionsof each of said multiple segments defining bias terminal ends of the arcuate shaped cavity enclosure provided in each segment, the surface of said bias ends being arranged parallel in relation with the bias ends of other of said segments so that when curling said body of the container upon longitudinal movement of the multiple segments to 9 10 entrain a marginal portion of the body into the cavity References Cited in the file of this patent enclosures, said terminal ends thereof cross the curl on the bias whereby the curl is formed and completed in UNITED STATES PATENTS the multiple cavities upon substantial abutment of said seastmm 1935 bias ends of each of said cavity enclosures with ends of 5 Mart? T '1942 corresponding cavity enclosures, means being provided Barblen 1942 to open a sectional part of each cavity enclosure for release of the completed curled portion of the container body from said cavities prior to retracting movement of said segments and truncated body part. 10 

